World’s oldest fossilised mushroom found

History is full of unlikely journeys, but none of them hold a candle to the journey taken by an ancient mushroom that lived on the earth as the supercontinent, Gondwana, was breaking apart.

The recent discovery was made in a limestone deposit in northeast Brasil, an incredibly rare find which has astounded scientists and stats nerds alike.

It’s thought to have fallen into a river that flowed to a saline lagoon before sinking to the bottom, where it was covered with many layers of fine sediment. After millions of years the mushroom’s tissues were mineralised, into fool’s gold, if you can believe it, which then even later transformed into goethite, a hydroxide mineral that has been used by humans over millennia to make ochre pigments. Thankfully, this precious mushroom has found its way to scientists rather than our cave-dwelling ancestors.

The discovery was made by palaeontologist, Sam Heads, from the Illinois Natural History Survey (INHS), while he was digitising a collection of fossils from the Brazilian site. He has said:

“Most mushrooms grow and are gone within a few days. The fact that this mushroom was preserved at all is just astonishing. When you think about it, the chances of this thing being here – the hurdles it had to overcome to get from where it was growing into the lagoon, be mineralised and preserved for 115 million years – have to be minuscule”

Most well-preserved ancient mushroom fossil specimens are found in amber deposits, formed as tree sap oozes out of wounds and breakages and covers small insects and vegetation alike – the mosquito in Jurassic Park, for instance. It’s a much more likely scenario for the preservation of a mushroom than the one found in Brazil.

Another INHS scientist, mycologist Andrew Miller, put the importance of the discovery well by saying:

“Fungi evolved before land plants and are responsible for the transition of plants from an aquatic to a terrestrial environment. Associations formed between the fungal hyphae and plant roots. The fungi shuttled water and nutrients to the plants, which enabled land plants to adapt to a dry, nutrient-poor soil, and the plants fed sugars to the fungi through photosynthesis. This association still exists today.”

The mushroom was classified in the agaric order and given the name Gondwanagaricites magnificus.